booster

booster
noun
  1. a thing or person that helps increase or promote something, in particular
    起推动(或推进)作用的事(或人),尤指
    ■(Medicine)a dose of an immunizing agent increasing renewing the effect of an earlier one
    (医)增强辅剂量
    ■the first stage of a rocket or spacecraft, used to give initial acceleration and then jettisoned
    (火箭,飞船的)助推器
    ■a device for increasing electrical voltage or signal strength
    (电压,电讯号的)增压器,放大器
    ■[incombination]a source of help or encouragement
    推动,鼓励
    job fairs are a great morale booster.
    人才交流市场大大地鼓舞了人心。
    ■(N. Amer.)a keen promoter of a person, organization, or cause
    (北美)积极的支持者;热心的拥护者
  2. (N. Amer. informal)a shoplifter
    (北美,非正式)(商店)窃贼,扒手
英语宝典
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